The Gregorian year always begins on January 1st and ends on December 31st. There is 365 days in ordinary year and 366 days in a leap year within its one year calendar. This type of calendar is the most common calendar used by people all around the world. Usually at the 4th quarter in every year, people are starting to look for a new calendar for the following year where they are preparing new plans or financial budget, vacations, events etc. Instead of looking for a new calendar every year, you can try to use this yearly calendar. This is a custom calendar where you can change its calendar dates automatically based on your input year. And with date markers custom function available in this calendar, you can type your important events and holidays in corresponding columns and see the date markers revealed automatically (blue for events, red for holidays).
There are US holidays date formula which also changed automatically based on input year. If you have recurring events every year, you can also type an excel function inside the event/holidays table. If you have some difficulties on doing that, just remember to modify it when the year is changed.